Surgical procedures frequently require cutting of tissue causing bleeding at the site of the cutting. Thus hemostasis is important in surgical procedures. Hemostasis is even more crucial in endoscopic or laparoscopic surgery where if the bleeding is not kept under control, the laparoscopy must be abandoned and the patient's body cut to perform open surgery so that inaccessible bleeding may be controlled.
Various techniques have been adopted to control bleeding with varying degrees of success, such as, for example, suturing, applying clips to blood vessels, stapling, as well as tissue heating, laser, electrocautery and ultrasonic techniques.
Surgical staplers have been used for tissue joining and to provide hemostasis in conjunction with tissue cutting. Such devices include, for example, linear and circular cutting and stapling instruments. Typically, a linear cutter has parallel rows of staples aligned in a cartridge with a slot through which a cutting means may pass between the rows of staples. This type of surgical stapler secures the tissue for improved cutting, joins layers of tissue, and provides hemostasis by applying parallel rows of staples to layers of surrounding tissue, as a cutting means cuts between parallel rows. These types of cutting and stapling devices have been used successfully in procedures involved in fleshy tissue such as, muscle or bowel, particularly in bowel resection procedures. Similarly, circular cutting and stapling devices have successfully been used, for example, in anastomotic procedures where a lumen is rejoined.
However, improvements are desirable with such cutting and stapling devices to optimize the hemostasis, particularly where the procedure involves cutting highly vascularized tissue, such as mesentery or adnexa, which is prone to having hemostasis problems.
Ultrasonically energized surgical instruments have been used to cut and simultaneously coagulate or cauterize tissue. Typically, such devices include a knife blade at the end of the instrument which receives and transmits ultrasonic energy at a therapeutic amplitude and frequency. Such devices may be used to cut and/or to cauterize tissue. However, these devices are sometimes difficult to use to manipulate tissue and achieve the desired cutting and/or coagulating effect.